File upload with Sinatra

upload.rb

require 'rubygems'
require 'sinatra'
 
get '/' do
  @files = Dir['public/*'].map {|f| File.basename(f) }
  erb :index
end
 
post '/upload' do
  filename = params[:file][:filename]
  file = params[:file][:tempfile]
 
  File.open("public/#{filename}", 'wb') {|f| f.write file.read }
 
  redirect '/'
end
 
__END__
@@ index
<h1>File upload!</h1>
<form action='/upload' method='post' enctype='multipart/form-data'>
<input type='file' name='file' /><br />
<input type='submit'/><br />
</form>
<hr />
<% @files.each do |file| %>
<a href='<%= file %>'><%= file %></a>
<% end %>